In a light emitting device which has a quantum well structure using a nitride semiconductor, a polarization electric field is generated inside the quantum well structure due to symmetrical property of a crystal structure of a nitride crystal and crystal strain, and carriers in the quantum well are separated spatially, which causes decrease in luminous efficiency and increase in a driving voltage.
Hence, in Patent Document 1, for the purpose of suppressing an influence of a piezo electric field, there is proposed a configuration which provides an n-type region doped with an n-type impurity and an undoped region in a barrier layer. However, even in the case of using this technology, the luminous efficiency is insufficient, and there is a room for improvement.